The Brain Vascular Malformation Consortium (BVMC) focuses on three relatively rare vascular malformations: Cerebral Cavernous Malformation (CCM), Sturge-Weber Syndrome (SWS), and Hereditary Hemorrhagic Telangiectasia (HHT). Each is poorly understood in terms of biological mechanisms, resource intensive to manage effectively, and has high probability of serious neurological morbidity, such as hemorrhage, seizures and focal neurological deficits. All three diseases share a common biological theme: a brain vascular phenotype based on failure of the normal physiological mechanisms of blood vessel formation or maintenance. Recent data also suggests that the three diseases share commonalities in their molecular signaling pathways. Each disease is characterized by a wide spectrum of phenotypes, for which biological risk factors are poorly understood. The identification of these risk factors would be of immediate significance for patient surveillance an for optimizing management. Further, although there are no specific medical therapies for these diseases, appropriate treatment trials will require biomarkers to risk stratify patients for selecton and surrogate outcomes. In our original project period, we established information-rich patient registries for all three diseases, and made significant progress towards the identification of MRI, genetic, and biochemical biomarkers associated with specific clinical outcomes. Based on this strong foundation, we now propose the renewal of the BVMC focused on three Specific Aims: 1) To continue to develop robust patient registries for HHT, SWS, and CCM; 2) To continue to identify and validate clinically relevant biomarkers for HHT, SWS, and CCM; and 3) To aid the development of future clinical research studies for HHT, SWS, and CCM. These aims will be accomplished through our three Projects, Cores, pilot project and training components, and active collaborations with the Patient Advocacy Groups - Angioma Alliance, Sturge Weber Foundation, HHT Foundation International - and the RDCRN Data Management and Coordinating Center. Establishment of the BVMC has been a major step forward in promoting cross-disease collaborations, providing a centralized clinical research infrastructure for studying these three rare diseases, and generating a valuable resource for the larger neurovascular community.